Digital image patch searching and matching, such as when matching patches between digital images, or between regions of the images, is also referred to as computing a nearest neighbor field and is a common technique used for image processing and computer graphics applications. Patches of an image may be compared as each pixel of the image, or patches may be a larger region of the image that includes a grid of multiple pixels. Patch matching can be time-consuming and processor intensive to search for a corresponding nearest neighbor database patch for every overlapping patch in an image, such as when comparing hundreds of thousands of image patches from an image to millions of external database image patches for nearest neighbor distance determinations. Some techniques leverage an approximate nearest neighbor search, such as on partition center patches of partitions of similar patches, in an effort to improve processor efficiency. However, even an approximate nearest neighbor search can be slow and processor intensive when attempting to search and match every image patch from an image to the external database patches.